US President Donald Trump tempered expectations of a Middle East deal by saying he had told his negotiators not to "rush", hours after his top diplomat said the US and Iran could strike a bargain to end the regional war as early as Sunday.Washington and Tehran have observed a ceasefire since April 8 while mediators push for a negotiated settlement, although Iran has imposed controls on Gulf shipping and the US has blockaded Iran's ports.On Sunday, during a visit to India, US Secretary of State Marco Rubio told reporters: "I do think perhaps there is the possibility that in the next few hours the world will get some good news." Trump, however, later said in a social media post: "I have informed my representatives not to rush into a deal in that time is on our side". "The Blockade will remain in full force and effect until an agreement is reached, certified and signed," he added.Earlier Trump had posted on social media that the deal "has been largely negotiated, subject to finalisation between the United States of America, the Islamic Republic of Iran and the various other Countries".Rubio said the agreement would start a "process that can ultimately leave us where the president wants us to be, and that is a world that no longer has to fear or worry about an Iranian nuclear weapon".Israeli Prime Minister Benjamin Netanyahu said on Sunday that he and Trump had agreed that "any final agreement with Iran must eliminate the nuclear threat entirely"."President Trump made clear that he will remain steadfast in the negotiations regarding his longstanding demand for the dismantlement of Iran's nuclear programme and the removal of all enriched uranium from Iranian territory, and that he will not sign a final agreement absent these conditions," an Israeli official, speaking on condition of anonymity, told AFP.- 'Seize this moment' -European leaders, keen to see Hormuz open and energy prices fall, welcomed the optimism early on Sunday. European Commission President Ursula von der Leyen hailed "progress towards an agreement", while Britain's Prime Minister Keir Starmer vowed to work with "international partners to seize this moment".